YARN-27. Fixed location of ms.start call

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1375083 13f79535-47bb-0310-9956-ffa450edef68

hadoop-yarn-project/hadoop-yarn/hadoop-yarn-server/hadoop-yarn-server-resourcemanager/src/test/java/org/apache/hadoop/yarn/server/resourcemanager/scheduler/TestQueueMetrics.java

@@ -238,11 +238,11 @@ public class TestQueueMetrics {
   @Test 
   public void testMetricsCache() {
     MetricsSystem ms = new MetricsSystemImpl("cache");
+    ms.start();
     
     try {
       String p1 = "root1";
       String leafQueueName = "root1.leaf";
-      ms.start();
 
       QueueMetrics p1Metrics =
           QueueMetrics.forQueue(ms, p1, null, true, conf);